This article explains fully how the president can legally wiretap US citizens without a warrant. It cites the law, something the left is loathe to actually do.
http://www.frontpagemag.com/Articles/ReadArticle.asp?ID=20621
I'm guessing that the alleged "secret Executive Order" that's apparently out there may be the "fix" for 1802 in terms of applying it to terrorist organizations and/or individuals.
I say this because PATRIOT Act II - which was filibustered last week - also included a fix or two for FISA, in particular making terrorist individuals subject to FISA without respect to an "organization", but again not really fixing the little hole or two in 1802.
If you read 50 U.S.C. s 1802, it clearly authorizes surveillance without a previous court order, but it also seems to require that the Attorney General immediately seek a court order authorizing the same.